Mystery smoke, need help identifying

[HotRaud90]

Upon arriving home from work a couple weeks ago, I noticed some smoke coming from up underneath the hood. Happened again today. Not thick smoke, very whispy...but enough to make me scratch my head and be a little worried. Opened the hood both times and inspected. Smoke seems to be comin from behind the upper and lower intake, even so much as lookin like it's comin from below the intakes back near the transmission. Transmission fluid is still nice and reddish pink. I've got no idea. Anyone got a clue? I sure don't.

[vegasmarauder]

Does it smell like oil or anti-freeze? The valley below the intake can collect the anti-freeze from a seeping COT at the front of the engine. There is a drain hole in the back of the block, but it can collect quite a bit before it drips out on the ground. There is a cooling tube that runs from the back of the water pump out to the heater core that is under the intake, but I have not seen a newer one leak (by the way, the special orange O rings are $10 ea from Ford, but When I have pulled high mileage engines apart there have been no leaks).

If water gets on the engine from heavy rain, etc. It can collect in the valley and may take a few days to all steam off out of there. The drain hole in the back of the block can get obstructed by debris and make it pool higher in the block valley under the intake.

[HotRaud90]

Does it smell like oil or anti-freeze? The valley below the intake can collect the anti-freeze from a seeping COT at the front of the engine. There is a drain hole in the back of the block, but it can collect quite a bit before it drips out on the ground. There is a cooling tube that runs from the back of the water pump out to the heater core that is under the intake, but I have not seen a newer one leak (by the way, the special orange O rings are $10 ea from Ford, but When I have pulled high mileage engines apart there have been no leaks).

If water gets on the engine from heavy rain, etc. It can collect in the valley and may take a few days to all steam off out of there. The drain hole in the back of the block can get obstructed by debris and make it pool higher in the block valley under the intake.

Hm. Well, it doesn't smell particularly like anything. Pretty neutral scent. The first time I ever noticed was very soon after I flushed my cooling system. I didn't really spill much antifreeze at all when fillin at the COT, but I guess that is a possibility with how recently I changed the coolant.

It definitely is more of like a steamy smoke...the type you would see when somethin gets real hot and then evaporates. The engine has not been wet recently and, like I said before, I didn't spill but a couple ounces of coolant at the COT at the flush...and my COT doesn't appear to be leaky either. Nice and tight and no signs of drips or stains.

Thanks for the info, btw. Good to know. Anyone else got any input?

[HotRaud90]

UPDATE: I was havin some weird issues with the A/C system tonight. Whenever I would turn on the Max A/C, it would start blowin out of the defrost vents, then intermittently switch to the front facing vents. It would switch back and forth between the two. EATC was real warm to the touch. And then, sure enough, more wispy smoke comin from under near the heater core and back towards the transmission. FUHHH. I know I'm not the only one with EATC demons. Can someone tell me what's goin on?

[tmwlch1]

I know around here if the AC is cold enough and the humidity is high we get a fog out of the vents. Kind of like dry ice in water fog.

[Blackened300a]

I'm going to say you should look into changing your EATC o-rings to cure the defrost/vent issue. I'm also pretty sure that the steam you are experiencing is condensation dripping onto the exhaust manifolds and evaporating. Drive the car without turning the AC on and see if you still experience the smoke you are describing.

[HotRaud90]

I'm going to say you should look into changing your EATC o-rings to cure the defrost/vent issue. I'm also pretty sure that the steam you are experiencing is condensation dripping onto the exhaust manifolds and evaporating. Drive the car without turning the AC on and see if you still experience the smoke you are describing.

Honestly, I've been wonderin if it was that. I'll see condensation on the A/C lines and then some drip spots elsewhere in the engine bay towards the back. You sayin that lets me know that my hypothesis is at least somewhat reasonable. Thanks.

Also, is changin the O-rings on the EATC a common replacement with the MM? Is them wearin out a common cause of the intermittent switch between the vents and defrost? Seems like I've seen info on it in a few different threads before but can't remember for sure.

[fastblackmerc]

Honestly, I've been wonderin if it was that. I'll see condensation on the A/C lines and then some drip spots elsewhere in the engine bay towards the back. You sayin that lets me know that my hypothesis is at least somewhat reasonable. Thanks.

Also, is changin the O-rings on the EATC a common replacement with the MM? Is them wearin out a common cause of the intermittent switch between the vents and defrost? Seems like I've seen info on it in a few different threads before but can't remember for sure.

Yes, the o-rings are a common issue.

[HotRaud90]

UPDATE: saw smoke again at the gas station. This time I found a very small puddle of fluid under the car. Inspected, found fluid drippin off the right side cat, around the trans. and oil pan, and off frame pieces that surround these parts.

Get home, get it on ramps, start inspecting. Find that the fluid is pinkish red - transmission. My immediate thought? "FUHHHH". Do some more inspecting, check tranny fluid levels and color. Correct levels and a nice pinkish red tone with no hint of brown. What gives? Start to look at filler neck, notice it's got wet stains all down the side. Look on underside near tranny fluid pan. Sure enough, a lot of the cooling lines and the filler neck are wet.

All that to find out that I think the dipstick was on there all cockeyed from the last time it was checked and the fluid was overflowin and runnin down the filler neck and onto everything else when at operating temp. Or possibly it got bumped loose because of it's extremely annoyin proxmity to a crap ton of other stuff up under the cowl.

Worst positioning place for a dipstick. But now I feel like the dipstick. Hopefully this is problem solved. Thanks for the input everyone.